Lorcaserin, a 5-HT(2C) receptor agonist, reduces body weight by decreasing energy intake without influencing energy expenditure.

Abstract

CONTEXT:

Lorcaserin, a selective 5-hydroxytryptamine (5-HT)(2C) receptor agonist, reduces body weight. It is unclear whether weight loss is due to reduced energy intake (EI) or also to enhanced energy expenditure (EE).

OBJECTIVE:

This study tested the effect of lorcaserin on EI and EE.

DESIGN, PARTICIPANTS, AND INTERVENTION:

In a double-blind, randomized, placebo-controlled trial, 57 (39 women) overweight and obese (body mass index, 27-45 kg/m(2)) adults were randomized to placebo (n = 28) or 10 mg twice daily lorcaserin (n = 29) for 56 d. Weight maintenance was imposed during d 1-7. Beginning on d 8, participants followed a diet and exercise plan targeting a 600 kcal/d deficit.

OUTCOMES:

At baseline and after 7 and 56 d of treatment, we measured body weight, body composition (dual x-ray absorptiometry), blood pressure, heart rate, EI at lunch and dinner, subjective appetite ratings, and 24-h EE and 24-h-respiratory quotient (RQ), measured by indirect calorimetry in a respiratory chamber.

RESULTS:

After 7 d of weight maintenance, EI was significantly (P < 0.01) reduced with lorcaserin but not placebo (mean ± sem for lorcaserin, -286 ± 86 kcal; placebo, -147 ± 89 kcal). After 56 d, lorcaserin resulted in significantly larger reductions in body weight (lorcaserin, -3.8 ± 0.4 kg; placebo, -2.2 ± 0.5 kg; P < 0.01), EI (lorcaserin, -470 ± 87 kcal; placebo, -205 ± 91 kcal; P < .05), and appetite ratings than in placebo. Changes in 24-h EE and 24-h RQ did not differ between groups, even after 24-h EE was adjusted for body weight and composition. Compared with placebo, lorcaserin had no effect on systolic or diastolic blood pressure or heart rate after 56 d.

CONCLUSIONS:

Lorcaserin reduces body weight through reduced EI, not altered EE or RQ.

• Authors: Corby K Martin, Leanne M Redman, Jinkun Zhang, Matilde Sanchez, Christen M Anderson, Steven R Smith, Eric Ravussin
• Journal: The Journal of clinical endocrinology and metabolism (J Clin Endocrinol Metab) Vol. 96 Issue 3 Pg. 837-45 (Mar 2011) ISSN: 1945-7197 [Electronic] United States
• PMID: 21190985 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Benzazepines
• Lipids
• Receptor, Serotonin, 5-HT2C
• Serotonin Receptor Agonists
• lorcaserin

Topics

• Adolescent
• Adult
• Aged
• Appetite (drug effects)
• Benzazepines (adverse effects, pharmacology)
• Blood Pressure (drug effects, physiology)
• Body Composition (drug effects)
• Body Mass Index
• Body Weight (drug effects)
• Double-Blind Method
• Energy Intake (drug effects)
• Energy Metabolism (drug effects)
• Female
• Heart Rate (drug effects, physiology)
• Humans
• Lipids (blood)
• Male
• Middle Aged
• Motor Activity (physiology)
• Obesity (drug therapy, psychology)
• Overweight (drug therapy, psychology)
• Oxidation-Reduction
• Receptor, Serotonin, 5-HT2C (drug effects)
• Serotonin Receptor Agonists (adverse effects, pharmacology)
• Surveys and Questionnaires
• Young Adult